sys: Remove $FreeBSD$: two-line .h pattern

Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

net: clean up empty lines in .c and .h files

sys: general adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

No functional change intended.

Completely rewrite the interface to smbdev switching from dev_clone
to cdevpriv(9). This commit changes the semantic of mount_smbfs
in userland as well, which now passes file descriptor in order to
to mount a specific filesystem istance.

Reviewed by: attilio, ed
Tested by: martymac

Change some variables from int to size_t. This is more accurate since
these variables represent sizes in one capacity or another. There is
no reason to allow negative numbers. Change userspace shared structure
elements that get used for the modified functions from int to uint32_t,
since it's not clear what userspace programs use these fields, and we
do not want to break binary compatibility. This fixes a panic when
corrupt or bogus data is passed into the kernel.

Obtained from: NetBSD
MFC after: 3 weeks

A new jail(8) with a configuration file, to replace the work currently done
by /etc/rc.d/jail.

Switch to our preferred 2-clause BSD license.

Approved by: bp

- Import the HEAD csup code which is the basis for the cvsmode work.

/* -> /*- for license, minor formatting changes

Use automatic major number allocation for nsmb devices.

This file also depends on sys/types.h and sys/ioccom.h.
Remove some old junk.

Submitted by: bde

Pull constants from netsmb/smb.h.

Import kernel part of SMB/CIFS requester.
Add smbfs(CIFS) filesystem.

Userland part will be in the ports tree for a while.

Obtained from: smbfs-1.3.7-dev package.